So I took some friends out this weekend in my '96 Prostar 205 LT1 for some tubing and fun. The boat ran normal as I was driving over to the spot where we usually tube on the river, I ran it through the motions mostly just to test it out and get used to it as it is only my 3rd time taking it out. I started off from idle and took off like I was pulling a skiier then cruised at about 3500rpm for a little bit and then took it up to about 4800 for about a minute just to make sure we were good at all speeds. After turning the boat off and swimming for about 30 minutes we got back in to tube. I was pulling a friend of mine who is about 240 lbs and his girlfriend about 110 lbs so not any crazy load. I took them through the first run for about 5 minutes of non aggressive tubing I'd say a 4 out of 10 on the tubing scale. Then the 240 lb'er decided he wanted to go on his own and challenged that I couldn't throw him off. So naturally I took the challenge and swung him back and forth at about a 7 out of 10 but never really exceeded 3500 rpm doing so. I was however powering through some turns. After about 2 or 3 minutes of pulling him through this I noticed I could not power over 3000 RPM's and when I tried to do so it was like the boat was keeping me from doing so, as if it was in a "limp mode". It didn't necessarily feel like the transmission was slipping just that it was keeping me from accelerating past 3000. So I took it out of gear and in neutral and the engine would rev up to 4800 RPM as it should. I also noticed at this time a whining sound coming from the bilge. I pulled the engine hatch and it sounded as if it was coming from the transmission. I then turned the boat off and immediately turned it back on, the whining stopped and the boat functioned perfectly. About two minutes later as I ran back down the lake I noticed the whining slowly getting louder from the bilge and again it would not go above roughly 3000 RPM. So I turned it off and back on again and it ran just fine again for another few minutes before having the same problem again. I checked the vitals of the engine and none of them were abnormal. Temp was about 120-140 the whole ride.

So from the circumstances that I encountered, it doesn't seem like clutch plates or anything like that. I am almost wondering if it is the pump that is for some reason not pumping enough fluid and there is a sensor that is putting it into limp mode, but I am not getting any Trans Temp light warnings or Check Engine lights coming on at all. I checked the fluid and it is at the perfect level. I am using the Dex/Merc fluid that was changed just prior to this launch btw. I have the Hurth ZF 450D. Does anyone have any advice for diagnosing the problem? Could it be excess vibration and a sensor that is causing it to limp? It seemed to be brought on by powering through turns (not power turns just normal tubing driving). The part that I am somewhat relieved by is that after 'resetting' the engine by turning it off and on it seemed to fix it at least for a minute which I am hoping is a sign of an easy fix and not a rebuild. Any help or advice would be appreciated. Sorry to be long winded but I figured if I armed you guys with all the info I had it may be easier to diagnose.

THANKS!

Last edited by Tateau18; 06-03-2013 at 05:55 PM.
Reason: Forgot to add some information.

The whining probably come from the fuel pump starving for fuel that would also explain the 3000 rpms.
I ll bet that your inlet screen at the fuel pump is clogged.
Very easy fix if that s your problem.
Let me find my how-to post!

The whining probably come from the fuel pump starving for fuel that would also explain the 3000 rpms.
I ll bet that your inlet screen at the fuel pump is clogged.
Very easy fix if that s your problem.
Let me find my how-to post!

I thought about this, but my only thing about the fuel filter is when I put the boat in neutral it will go to WOT no problem. Does the computer have a limp mode for issues with the transmission?

It revs fine in neutral because there is no load on the engine.
Please,check that inlet screen.It takes 15 minutes to do.
Your transmission is fine if it s not slipping.
All your symptoms point towards fuel starvation,the whinning from the pump,rpms drop,
rpms fine in neutral...
Good luck!

Edit:Not talking about the fuel filter but the inlet side screen in the pump itself! Since the filter is AFTER the pump,often the screen will get blocked before the filter do.

Tateau18 and Andre, do either of you have pictures of how to check that filter?

I had the same issues yesterday on our '06 X-45/L18. I was going to post a video, but it's exactly like the viedo that StrmChzr posted.

Andre, on the other thread you posted these instuctions:

Unplug battery. Easy enough
Close manual shut off valve on top of tank. Where is this?
Remove electric connector from pump. I imagine I can find this. Is it a canon-plug type connector?
Remove hoses and tubing from pump.Use rags or small container for whatever will drop. Why do this? Is the screen filter an in-line thing you can only get to with the hoses off?
Remove the brass fitting,inlet side. Any pictures of this?
Clean the screen.
Check that!
Take your filter to any car parts dealer for an instant replacement... Do you do this only if the screen filter is ruined?
__________________

The "brass fitting, inlet side" you mention ("clean the screen"), you must remove the pump from the module to clean this screen, correct?

Since the responses are a little quiet so far, I will do what I can. The fuel pump on the '96 205 above is mounted on the rear of the engine and is an entirely different setup from what I assume is in your boat. I believe your pump is submerged in your fuel tank like the one in the fuel pump 101 thread.

Since the responses are a little quiet so far, I will do what I can. The fuel pump on the '96 205 above is mounted on the rear of the engine and is an entirely different setup from what I assume is in your boat. I believe your pump is submerged in your fuel tank like the one in the fuel pump 101 thread.

Good luck with your diagnosis/repair.

+1 on the explanation on the Fuel pump 101 thread. In addition, check RockAuto the come for the replacement Airtex pump for the Carter OEM.

__________________...A bad day water skiing still beats a good day at work...1995 Pro Star 205....